"We have to believe that (we can win gold in Rio) and we do believe that," Gemili told British media.
"We work so hard as a team, we've had a lot of good trips this year for bonding, we are in the sport to win. We don't want to be making up the numbers, we want to be challenging to be the best."
Britain were disqualified from the men's 4x100 metres relay for the fourth time in five Olympics at London 2012, but were the winners at the 2004 Games in Athens.
(Reporting by Ian Rodricks in Bengaluru; Editing by Alison Williams)
